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kqt1989
11-01-2018, 03:26 PM
Hi everyone, I'm in the process of designing the steering system. My goal is to reduce the steering effort from last year's design. One of the change that I'm going to make is using the single U joint instead of double U joint. Is anyone have any idea that the single U joint would be better than the double Ujoint ?
The reason the double u joint was used last year is because the angle between the steering column and the steering rod was to stiff ( close to 90 degree ) this year, we are be able to have a flatter angle.

BillCobb
11-01-2018, 04:08 PM
Your's car's 'steering effort' problem is a design issue, not a disease. A couple of questions, first:

Who are you and what team ? (To beat Claude to the question).

What are the measurements of your steering effort (rim force) for 0+ kph and for a higher speed condition at several g's Ay. You would use a constant radius circle, a speed measuring device (or a stop watch) and a fish scale to get some data.

What is the targeted steering effort for these maneuvers ? You should do some subjective evaluations from driver candidates to establish these goals.

Then:

The single U-joint offers you the possibility of using joint angle and phasing to produce harmonic rim force variation. That means low straight ahead and high at max Ayg or the other way around.

Other factors for design studies should be obvious: front axle weight, tire brand, size, construction and pressure, overall steering ratio, caster and kingpin angles and scrub radius.

Now you will have all the ingredients for a spreadsheet to analyze rim force. Ask it what settings should be made to make the car meet your goals. There will be several, so you will need to provide weighting function values on input parameters that might be constrained by other subsystem requirements.

Claude Rouelle
11-11-2018, 04:28 PM
kqt1989..... Not worth to introduce your self? Just a question of courtesy and politeness...

That being said....

Check https://www.facebook.com/search/top/?q=claude%20rouelle%20steering%20column

You also want to look at https://www.youtube.com/watch?v=Idk3BVDVHq4 Drive shaft and steering column are not different issues.